<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			#a{
				width: 100px;
				height: 100px;
			}
			
			div{
				height: 200px !important;				
				background: red;
			}
				
			
		</style>
	</head>
	<body>
		<div id="a">!important是最高权重</div>
	</body>
</html>
